
ZSYR(l) ) ZSYR(l)
NAME
ZSYR  perform the symmetric rank 1 operation A := alpha*x*( x' ) + A,
SYNOPSIS
SUBROUTINE ZSYR( UPLO, N, ALPHA, X, INCX, A, LDA )
CHARACTER UPLO
INTEGER INCX, LDA, N
COMPLEX*16 ALPHA
COMPLEX*16 A( LDA, * ), X( * )
PURPOSE
ZSYR performs the symmetric rank 1 operation A := alpha*x*( x' ) + A, where alpha is a
complex scalar, x is an n element vector and A is an n by n symmetric matrix.
ARGUMENTS
UPLO  CHARACTER*1
On entry, UPLO specifies whether the upper or lower triangular part of the array A
is to be referenced as follows:
UPLO = 'U' or 'u' Only the upper triangular part of A is to be referenced.
UPLO = 'L' or 'l' Only the lower triangular part of A is to be referenced.
Unchanged on exit.
N  INTEGER
On entry, N specifies the order of the matrix A. N must be at least zero.
Unchanged on exit.
ALPHA  COMPLEX*16
On entry, ALPHA specifies the scalar alpha. Unchanged on exit.
X  COMPLEX*16 array, dimension at least
( 1 + ( N  1 )*abs( INCX ) ). Before entry, the incremented array X must contain
the N element vector x. Unchanged on exit.
INCX  INTEGER
On entry, INCX specifies the increment for the elements of X. INCX must not be
zero. Unchanged on exit.
A  COMPLEX*16 array, dimension ( LDA, N )
Before entry, with UPLO = 'U' or 'u', the leading n by n upper triangular part of
the array A must contain the upper triangular part of the symmetric matrix and the
strictly lower triangular part of A is not referenced. On exit, the upper triangu
lar part of the array A is overwritten by the upper triangular part of the updated
matrix. Before entry, with UPLO = 'L' or 'l', the leading n by n lower triangular
part of the array A must contain the lower triangular part of the symmetric matrix
and the strictly upper triangular part of A is not referenced. On exit, the lower
triangular part of the array A is overwritten by the lower triangular part of the
updated matrix.
LDA  INTEGER
On entry, LDA specifies the first dimension of A as declared in the calling (sub)
program. LDA must be at least max( 1, N ). Unchanged on exit.
LAPACK version 3.0 15 June 2000 ZSYR(l) 
